I’m always looking for ways to increase the processing power for my LED projects. After getting through several Raspberry Pi SBC’s, I finally needed a more compact solution for running the accompanying software that drives many of my projects. I have a few “wearable” projects lined up, and while the rPi A+ is nice and small, it lacks quite a few of the features I am after, like battery charging, networking, etc.

Even with the (unofficial, and very unfortunately discontinued) ODroid-W from HardKernel (known for the ODroid-X platforms), long shipping times and a relatively high price-point make it a less-than-favourable alternative to the highly integrated Edison platform, which I can have delivered overnight from all the usual suppliers (RS, Digikey, etc).

What’s better than one Edison? 4 Edisons!

The Edison platform was designed with the Yocto project in mind. I have yet to fully dive into Yocto, but what I do know is that it is designed to allow users to create very streamlined, pre-built Linux distributions, that contain only what is needed for the actual product application. Sounds neat, but I need to have quite a bit of a play before I know what to “bake” into a Yocto image that satisfies all my requirements. So what do we do while trying to understand the Yocto ecosystem? Install Debian and have a play of course! I’ll detail my findings over this post, and hopefully point out a few ‘gotchas’ that caused me to scratch my head. (more…)

Having seen the work done by cpldcpu on the APA102 LED chipset, I thought I’d test out some of my strips using his code on an ATMEGA328p. A quick project using his driver routines with a HSV/RGB Converter class proved a success.

Phwoar. This one took some pretty crafty wiring! 1,920 Individually addressable LEDs, arranged in a cylindrical 32 x 60 matrix. Peak power consumption for this baby is ~580W of blinding glory. A few more photos after the break, I’ll try and get some build details up soon.

So this year, my halloween options are either an interesting mask idea, or Krieger. I’m going to try the mask idea first, because I’d rather build something than just stick on a lab coat, and I’m also going to a burlesque ball, so the Krieger thing is a little off the mark…

I have this filigree metal mask left over from a party last year, and I thought it’d be pretty cool to see if I could find a way to bring it to life. Here it is, in it’s stock form.

So, what can I do to add a little life to it, and get it looking something more like… this:

This is to be a build log of the first commission I’ve decided to document. This is a custom piece, requested after my name was suggested for the job. It’s a mainly polycarbonate theatrical staff, with the crown adorned with UV LEDs. It’s rechargeable, and has a small microcontroller to handle battery management and sequencing of the LEDs.

A photo of the LED “crown”, taken during the build process.

Read on for more photos of the construction, and a few bits of technical info that make the project what it is.

Here’s a little board I knocked up in EAGLE, that I created to allow me to easily spin up BLDC motors that are often found in hard disk drives. I fabbed the boards with OSHPark, and finally finished soldering them up this week. A quick test indicates success!

Spinning away nicely.

The board is based on a DRV11873 from TI. It’s a nice little chip, and takes a lot of the work out of just getting the motor to spin. If you can’t afford the processor resources to drive the motor, you can offload that function to this IC, and control speed simply with a single PWM channel.

I’ve spent a bit of time away from here lately. Well, I haven’t, I’ve written a few updates to post, but they are all missing a few photos / conclusions, so more from them later.

Things to come:
– JTAG on the ATMEGA2560
– Moving on from the Arduino Platform – AVR’s
– Updates on the GlowStaff project
– A crash course on driving brushless DC Motors
– And a few other bits and pieces.

I’ve got some holiday coming up shortly, so I’ll do my best to get all of those posted up then!

I was pretty pleased with how my last project turned out, so I’ve started working on another idea with a different friend, for her to wear to another party in late Jan. I’m glad to have a little more time on this one, because it’s looking like it will be a little more complex! The image below is the result of a few hours of brainstorming in SketchUp, and will also be one of the few electro-mechanical projects that I have done.

Some people have a passion for a certain something. Mine is building things. My friend’s passion is fairies… It’s an odd set to combine, but I think I can come up with something pretty cool here. She want’s a set of fairy wings to take to this party. Sure, you can buy wings from costume shops, but that’s no fun! I want to design something a bit more special then that! So, I sat down and thought of what would give that special something to the design.

I like LED lighting, so there will definitely be some of that involved. I had originally planned to use EL wire, for it’s unique appearance, but I got tired of looking for small-footprint solutions for reliably powering the EL strings. Besides, it’s somewhat fixed in it’s colour output, and that can be quite restrictive! I’ll explain what I’m using instead later on.

That’s not the final touch though. Shortly after the lighting, I got to thinking, can I get these wings moving? What you see above is the base of that idea. Using a couple of RC servos, and some ball bearings, it should be possible! I’m going to be working on finalizing the design over Christmas, which will leave me most of January to order and build.

I’ll be keeping track of the work here, so check back for more updates!

My friend rocking the finished dress. I didn’t manage to get many photos myself, and I’m still waiting to see others from the ball, so this will have to do for now. It looks a lot more purple in the photos, I think there’s a fair amount of UV light coming out of the blue LED elements. I’ll stick more photos up when they arrive!

Countdown…

Well, that went quickly! I’m now at T-2 days until the night of the ball, and thankfully, all my eBay bits have arrived in time! (Aside from a mild nuisance of some wrongly delivered NPN transistors, more on that later…) Here’s what my test bench looked like yesterday, with some basic debugging going on.

Bench Testing The Controller with the LED strips.

As of this evening, I’ve gotten the controller PCB built and working, with a nRF24L01+ radio for user interaction, and I’ve prototyped a pretty solid menu structure for controlling the pattern and brightness. I say prototyped, as I’ve hit a little math (I think!) snag when moving the code over from my Atmega2560 dev platform, to the 328p-based controller, but I hope to have cracked it by tomorrow.